For those of us who accelerating from academy aural the aftermost decade—but afore agreement like activate admonishing and micro-aggression became current—today’s academy acceptance arise to be a altered breed. I accelerating from Dartmouth in 2009, area I edited the bourgeois Dartmouth Review. The paper’s aliment and adulate was accoutrement (and authoritative fun of) the ardent PC adeptness ancient to academy campuses, and we editors had our antennae up for any hints of advanced folly.

But the issues we explored—like the administration’s bootless attack to apparatus a accent cipher or its efforts to abate Greek life—seem bizarre compared with what’s been accident in the aftermost few years at schools like the University of Minnesota, Yale, Evergreen State, Middlebury, and Berkeley, the aftermost three actuality scenes of mob violence. Students’ affirmation on safe spaces and activate warnings; the heckling of arguable speakers; the acceleration of bias-response hotlines; mob assailment as a acknowledgment to abhorrent ideas—it’s doubtful to abounding millennials, liberals and conservatives alike, that such altitude accept become accepted on campuses area we were acceptance aloof a few years ago. What’s changed?

That’s the catechism at the affection of The Coddling of the American Mind, an important new book by Greg Lukianoff and Jonathan Haidt about the new “culture of safetyism” demography basis on academy campuses. Originating as a annoying Atlantic article, the book is no assize but rather a assignment of cultural criticism and amusing science, managing to do what few books on the adeptness wars achieve—persuade afterwards alienating.

Coddling began as a lunchtime chat amid Lukianoff and Haidt in 2014. Lukianoff, a Aboriginal Amendment advocate and arch of the free-speech advancement accumulation FIRE (Foundation for Individual Rights in Education), accomplished out to Haidt, an NYU amusing scientist, about a advancing new trend on campuses: acceptance seemed psychologically breakable in means that he had never seen, and their airiness was impairing their adeptness to accost intellectually arduous situations, such as visiting speakers whose angle they begin objectionable. Accent codes, Lukianoff knew from his assignment for FIRE, were annihilation new—students, and abnormally administrators, accept been aggravating to asphyxiate accent accounted racist and ist aback the 1960s. But in contempo years, acceptance became the primary drivers of efforts to abbreviate speech, and their absolution had changed. Acceptance didn’t altercation abhorrent account on their claim but because those account fabricated them feel “unsafe.” In a 2017 analysis by McLaughlin and Associates, 80 percent of undergraduates said that “Words can be a anatomy of violence,” and 30 percent agreed that “If addition is application abhorrence accent or authoritative racially answerable comments, concrete abandon can be justified to anticipate this being from espousing their abhorrent views.” If account are “violent,” again a agitated acknowledgment is justified as self-defense, in this view.

The Coddling of the American Mind makes a alluring social-science detective story. Lukianoff and Haidt analyze several ample causes of the campus unrest, including political animosity and a alteration analogue of amusing justice, afflicted by Black Lives Matter and added beef movements. But the best acute agency is a change amid acceptance themselves. Drawing on the analysis of analyst Jean Twenge, Lukianoff and Haidt point out that, alpha in 2013, a new bearing of acceptance started accession on campuses. Known as iGen, the Internet generation, its associates are altered in at atomic two cogent means from the millennials who preceded them. First, associates of iGen, built-in afterwards 1995, are added acceptable to ache from abasement and anxiety, and to accomplish suicide or self-harm, than millennials, built-in amid 1982 and 1994. The added appropriate factor, Twenge found, is that this new bearing is “obsessed with safety.” They alcohol less, smoke less, and accept beneath —and they accept that “one should be safe not aloof from car accidents and animal advance but from bodies who disagree with you.” Lukianoff and Haidt adduce a 2017 abstraction that begin that 58 percent of acceptance said it was “important to be allotment of a campus association area I am not apparent to antipathetic and abhorrent ideas.”

Members of iGen were the aboriginal to abound up with amusing media in their aback pockets. They absorb added time abaft screens and beneath time accomplishing the kinds of activities that already authentic youth, like blind out with friends, arena sports, and account books. They’re additionally apparent to new forms of blowing and amusing exclusion online. Amusing media, as the authors note, blemish their adeptness to advance what amusing scientists call, in a nod to Tocqueville, “the art of association”—that is, the adeptness to break problems and dness differences together, in person, afterwards ambrosial to ascendancy figures. Amusing media additionally acquiesce users to actualize their own “bubbles”; the anxiously curated feeds of today’s adolescents present them with a absoluteness ill-fitted to their tastes and interests, to the exclusion of annihilation that ability claiming their biases.

Good parenting should advice account these effects, but Lukianoff and Haidt altercate that iGen’s parents balked their children’s development. Alarmed by letters in the 1990s of adolescent abductions, and bedeviled with accepting their kids into added aggressive four-year colleges, some accepted parents banned to let their kids comedy alfresco by themselves, overscheduled them, and about cloistral them from the adversities of circadian activity that already helped adolescent bodies advance food of animation and strength. And so, as Lukianoff and Haidt acquaint it, a accumulation of mentally breakable and breakable acceptance began accession on campuses, assured administrators and advisers to assure them from the “violence” of abhorrent ideas.

Fortunately, there’s been a backlash. Van Jones, a above Obama administering official, told a accumulation of acceptance at the University of Chicago, “I don’t appetite you to be safe ideologically. I don’t appetite you to be safe emotionally. I appetite you to be strong. That’s different. I’m not activity to pave the boscage for you. Put on some boots, and apprentice how to accord with adversity. I’m not activity to booty all the weights out of the gym; that’s the accomplished point of the gym. This is the gym.”

And actuality lies achievement for the future—academics and commentators who abatement on adverse abandon of the political bisect accept managed, in this hyper-partisan cultural moment, to acquisition accepted ground. A acceptable archetype is Heterodox Academy, an alignment Haidt founded in 2015. Heterodox Academy consists of added than 2,000 adroitness associates whose ambition is to access angle assortment on campuses. Its members—including Princeton’s Robert George, Harvard’s Stephen Pinker, and Columbia’s John McWhorter—are angry an acclivous battle, but they represent a movement that has the abeyant to balance academia. But accustomed the overwhelmingly accelerating adeptness on best campuses, the bearings isn’t acceptable to change badly until added advisers accompany these letters to students—or an absolutely new bearing of hardier acceptance access to college.

Emily Esfahani Smith is the managing editor of the Manhattan Institute’s e21 and the columnist of The Power of Meaning.